Hollow building-block.



BEST AVAiLABLE cop,

PATB-NTEP, 0GT. 3,- 1905.

11. s. PALMER. v HOLLOW BUILDING BLOCK. APPLICATION riLnn 1.13.24, 1904.

v 5. x I

BEST AVAlLA-BLE CUP.

UNITED ST T S.

PATENT OFFICE.-

HARMQN s. PALM RQ I i-WASHINGTON, DISTRICT or COLUMBIA.

" 1 IHQLILOW'BUILDING-BLOCK. I

.To all whom, it may concerns Be it known that I. HARMON S. PALMER, a

- citizen of the United States-residing at Washington, in the District of Ooluiill'ii'a, liave'invented new and useful Improvements in'Hollow Building-Block's, of which the'following is asp'ecification.

j My invention relates to improvements in hollow building-blocks; and itsobje'et'isto provide a block of increased durability.

The inventionis illustrated in the accompanying drawings, in which v Figure 1 is a perspective view of. ahollow building-block cons'tructedin accordance with I proper, 71 represents holes' forme'd thereingt and 0 represents recesses formed in the-ends my improvements, and Fig. 2-is a central and vertical section of the sam blo k v Referring to the drawings, a is the'block of the block. On the snj'jaces of the block -'within 1 these holes andvrecesses isi formed 'by phalt, coal-tar, 1 or :other suitable moistureproof material. By thisconstruction'th-block is rendered impermeable to moisture through Spe ification of Letters Patent. Application filed Inch 24,1904. Serial m. }99,818.

Patented Oct 3, 1905.

the spaces forming the central holes and recesses of the block.

. Having thus described my invention, what I claimis.

- An artificial hollow bnilding-block havf 'ing a' central hole adapted-to register with a hole of a corresponding similar blockand having a coating of plastic moisture-proofmate rial on the walls of said hole whereby a-protective lining is afl'ordedfor the block and the inner air space extending through the. .v

blocks maintainedin a dry state; substan-' 2.'Abuilding-block provided with a cen:

tral hole and with recessesadapted. toregis -ter with similar recesses inan adjoining block' and a coating of a plastic moisture-proof matiallyas described.

terial onthe walls of said hole and recesses-{f ,5 substantially as and for the purpose described."

. In testimony whereofI have signed m I ZWitnesses: .I

-Jos. H'..BLAcKwoo1 4 w v I v H. R Doom rrnnti-hf lj "to this specification in the presence'of two sub: 3 

